Freeze Warning 1, NWS Tucson, AZ

494 
WWUS75 KTWC 200500
NPWTWC

URGENT - WEATHER MESSAGE
NATIONAL WEATHER SERVICE TUCSON AZ
1000 PM MST MON MAR 19 2012

AZZ504-506-201300-
/O.CON.KTWC.FZ.W.0001.120320T0900Z-120320T1500Z/
TUCSON METRO AREA-SOUTHEAST PINAL COUNTY-
INCLUDING THE CITIES OF...TUCSON...GREEN VALLEY...MARANA...VAIL...
MAMMOTH...ORACLE
1000 PM MST MON MAR 19 2012

...FREEZE WARNING REMAINS IN EFFECT FROM 2 AM TO 8 AM MST
TUESDAY...

A FREEZE WARNING REMAINS IN EFFECT FROM 2 AM TO 8 AM MST TUESDAY.

* TIMING...LOW TEMPERATURES OF 30 TO 32 DEGREES ARE FORECAST TO 
  OCCUR TUESDAY MORNING WITH TEMPERATURES DROPPING BELOW 
  FREEZING AS EARLY AS 2 AM AND WARMING ABOVE FREEZING BY 8 AM. 

* IMPACTS...SUB FREEZING TEMPERATURES ARE LIKELY WHICH COULD 
  CAUSE CROPS OR SENSITIVE VEGETATION TO BE KILLED. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FREEZE WARNING MEANS SUB-FREEZING TEMPERATURES ARE EXPECTED. THESE
TEMPERATURES WILL KILL SENSITIVE CROPS AND VEGETATION. COVER
THEM...IF POSSIBLE...WITH CLOTH SHEETS OR BLANKETS TO PROTECT THEM
FROM FREEZING.

&&

$$

989 
WWUS75 KTWC 201000
NPWTWC

URGENT - WEATHER MESSAGE
NATIONAL WEATHER SERVICE TUCSON AZ
300 AM MST TUE MAR 20 2012

AZZ504-506-201500-
/O.CON.KTWC.FZ.W.0001.000000T0000Z-120320T1500Z/
TUCSON METRO AREA-SOUTHEAST PINAL COUNTY-
INCLUDING THE CITIES OF...TUCSON...GREEN VALLEY...MARANA...VAIL...
MAMMOTH...ORACLE
300 AM MST TUE MAR 20 2012

...FREEZE WARNING REMAINS IN EFFECT UNTIL 8 AM MST THIS MORNING...

A FREEZE WARNING REMAINS IN EFFECT UNTIL 8 AM MST THIS MORNING. 

* TIMING...LOW TEMPERATURES OF 28 TO 32 DEGREES ARE FORECAST THIS
  MORNING WITH TEMPERATURES ALREADY BELOW FREEZING IN SOME
  LOCATIONS.

* IMPACTS...SUB FREEZING TEMPERATURES ARE LIKELY WHICH COULD 
  CAUSE CROPS OR SENSITIVE VEGETATION TO BE KILLED.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FREEZE WARNING MEANS SUB-FREEZING TEMPERATURES ARE EXPECTED.
THESE TEMPERATURES WILL KILL SENSITIVE CROPS AND VEGETATION.
COVER THEM...IF POSSIBLE...WITH CLOTH SHEETS OR BLANKETS TO
PROTECT THEM FROM FREEZING.

&&

$$

218 
WWUS75 KTWC 201456
NPWTWC

URGENT - WEATHER MESSAGE
NATIONAL WEATHER SERVICE TUCSON AZ
756 AM MST TUE MAR 20 2012

AZZ504-506-201600-
/O.EXP.KTWC.FZ.W.0001.000000T0000Z-120320T1500Z/
TUCSON METRO AREA-SOUTHEAST PINAL COUNTY-
INCLUDING THE CITIES OF...TUCSON...GREEN VALLEY...MARANA...VAIL...
MAMMOTH...ORACLE
756 AM MST TUE MAR 20 2012

...FREEZE WARNING WILL EXPIRE AT 8 AM MST THIS MORNING...

THE FREEZE WARNING WILL EXPIRE AT 8 AM MST THIS MORNING. 

TEMPERATURES OVER THE WARNING AREA ARE AT OR ABOVE 32 DEGREES AND
CONTINUE TO WARM. AS SUCH...THE FREEZE WARNING WILL BE ALLOWED TO
EXPIRE.

$$

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
857 AM MST MON MAR 19 2012

.SYNOPSIS...CONTINUED COLDER WITH PERIODS OF SHOWERS TODAY...ENDING
BY LATER THIS EVENING. SNOW LEVELS LOWERING TO NEAR VALLEY FLOORS AT
TIMES TODAY. NEAR OR BELOW FREEZING IN MANY LOCATIONS TONIGHT WITH
FROST POSSIBLE. DRY CONDITIONS WILL RETURN THE SECOND HALF OF THE
WEEK WITH A STRONG WARMING TREND.

&&

.DISCUSSION...UPPER LOW CENTER NOW OVER CENTRAL/NORTHERN ARIZONA
WITH SOUTHEAST ARIZONA ON THE SOUTHERN PERIPHERY OF THE UPPER LOW.
THIS IS A VERY COLD SYSTEM...ESPECIALLY FOR MID TO LATE MARCH WITH
500 MB TEMPERATURES BASED ON 12Z KTWC SOUNDING AT -28C. LATEST RADAR
IMAGERY SHOWS FAIRLY WIDESPREAD SHOWER COVERAGE FROM CENTRAL PIMA
COUNTY EASTWARD. THESE ARE VERY CONVECTIVE IN NATURE AND WE'VE
ALREADY HAD A FEW CALLS FROM SPOTTERS IN THE TUCSON METRO AREA OF
GRAUPEL/SNOW PELLETS AS THESE SHOWERS HAVE MOVED THROUGH. SNOW
LEVELS ARE NOW AT ABOUT 3000-3500 FEET AND WILL GENERALLY REMAIN
3000-4000 FEET TODAY BUT CAN BRIEFLY LOWER TO ABOUT 2500-3000 FEET
IN HEAVIER SHOWER ACTIVITY. MEANWHILE...SHOWER ACTIVITY CONTINUES TO
FILL IN NICELY AS ADDITIONAL ENERGY DIGS INTO THE BASE OF THE TROUGH
THANKS TO A 150+KT JET STREAM ON THE BACK SIDE OF THE TROUGH. WHILE
QPF AMOUNTS WILL NOT BE HIGH TODAY...THERE WILL BE ISOLATED
LOCATIONS IN THE WINTER STORM WARNING AREA ABOVE 3000 FEET THAT WILL
SEE A QUICK BURST OF AN INCH OR TWO OF SNOW. THUS...WILL MAINTAIN
WINTER STORM WARNINGS ABOVE 3000 FEET WHICH GO THROUGH 8 PM. THE
MORE SIGNIFICANT IMPACT FOR THIS EVENT WILL CERTAINLY BE IN THE
LOWER ELEVATIONS WHERE SNOW IS QUITE UNUSUAL AS OPPOSED TO THE
MOUNTAINS WHERE SEVERAL OF SNOW IS VERY COMMON.

EXPECT PRECIPITATION TO END FROM NORTHWEST TO SOUTHEAST THIS EVENING
AS THE TROUGH BEGINS TO PULL AWAY. BASED ON RECEIPT OF LATEST 12Z
GUIDANCE...DO EXPECT SKIES TO AT LEAST PARTIALLY CLEAR IF NOT BECOME
MOSTLY CLEAR OVERNIGHT. MORNING LOW TEMPERATURES WILL BECOME A
CONCERN FOR THE LOWER ELEVATIONS AS THEY NEAR FREEZING ALONG WITH
SOME FROST CONCERNS. WILL TAKE A CLOSER LOOK AT THIS FOR THE
AFTERNOON PACKAGE AND CONSIDER FREEZE WARNINGS AS APPROPRIATE.

DRIER WEATHER WITH WARMING TEMPERATURES ARE THEN EXPECTED TO MOVE IN
FOR THE REMAINDER OF THIS WEEK.

&&

.AVIATION...SCT-BKN CLOUD DECKS GENERALLY 4-9K FT AGL. SCT
-SHRA/ISOLD TS/PL NORTH OF TUCSON THROUGH 19/06Z. -SHRA FAIRLY
WIDESPREAD THROUGH THIS AFTERNOON WITH  SNOW LEVEL LOWERING TO
AROUND 3KFT AGL. MVFR AND IFR CONDS WILL ALSO INCREASE. SFC WINDS
10-25 KTS...STRONGEST NEAR SHOWERS. AVIATION DISCUSSION NOT UPDATED
FOR TAF AMENDMENTS.

&&

.FIRE WEATHER...SUNDAYS WIDESPREAD VALLEY RAIN AND MOUNTAIN SNOW
HAVE DIMINISHED ANY FIRE WEATHER CONCERNS. WILL AGAIN SEE PERIODS OF
VALLEY RAIN AND MOUNTAIN SNOW AT TIMES TODAY. DRY CONDITIONS AND
CALMER WINDS WILL RETURN TUESDAY THROUGH SATURDAY ALONG WITH A
STRONG WARMING TREND.

&&

.CLIMATE...HIGHS TODAY WILL BE RATHER CHILLY WITH MOST OF THE AREA
NOT GETTING OUT OF THE 40S. LOOKING AT THE TUCSON HISTORICAL
TEMPERATURE RECORDS FOR MARCH...THE OFFICIAL RECORDING SITE HAS
RECORDED HIGHS IN THE 40S ONLY 13 TIMES IN 118 YEARS OF TEMPERATURE
RECORDS. THE RECORD LOW MAXIMUM TEMPERATURE FOR MARCH 19TH IS 50
DEGREES BACK IN 2006.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...

    WINTER STORM WARNING UNTIL 8 PM MST THIS EVENING FOR LOCATIONS
    ABOVE 3000 FEET INCLUDING AZZ503-504-506>515.

&&

WEATHER.GOV/TUCSON

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TUCSON AZ
453 AM MST MON MAR 19 2012

AZZ501>515-201200-
WESTERN PIMA COUNTY-TOHONO O'ODHAM NATION-
UPPER SANTA CRUZ RIVER VALLEY/ALTAR VALLEY-TUCSON METRO AREA-
SOUTH CENTRAL PINAL COUNTY-SOUTHEAST PINAL COUNTY-
UPPER SAN PEDRO RIVER VALLEY-
EASTERN COCHISE COUNTY BELOW 5000 FEET-UPPER GILA RIVER VALLEY-
WHITE MOUNTAINS OF GRAHAM AND GREENLEE COUNTIES-
GALIURO AND PINALENO MOUNTAINS-CHIRICAHUA MOUNTAINS-
DRAGOON AND MULE AND HUACHUCA AND SANTA RITA MOUNTAINS-
CATALINA AND RINCON MOUNTAINS-BABOQUIVARI MOUNTAINS-
453 AM MST MON MAR 19 2012

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST
ARIZONA.

.DAY ONE...TODAY AND TONIGHT

A WINTER STORM WARNING IS IN EFFECT ABOVE 3000 FEET UNTIL 8 PM.
SNOW LEVELS MAY FALL AS LOW AS 2500 FEET AT TIMES. CLEARING FROM
THE WEST TONIGHT WILL ALLOW WIDESPREAD NEAR FREEZING TEMPERATURES
ACROSS MOST OF THE AREA WITH A HARD FREEZE IN EASTERN VALLEY
LOCATIONS. AREAS OF FROST ARE ALSO POSSIBLE LATE TONIGHT AND EARLY
TUESDAY MORNING.

PLEASE SEE SPECIFIC WATCH...WARNING AND ADVISORY PRODUCTS FOR
ADDITIONAL INFORMATION.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

VERY COLD TUESDAY MORNING WITH AREAS OF FROST POSSIBLE. MOST
LOCATIONS WILL BE NEAR OR BELOW FREEZING. DRY AND WARMER THE REST
OF THE WEEK INTO THE WEEKEND.

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.

WEATHER.GOV/TUCSON